https://bugs.freedesktop.org/show_bug.cgi?id=84648
Bug ID: 84648 Summary: Lag/Pause When VRAM->GTT or GTT->VRAM transfer occur Product: Mesa Version: git Hardware: x86-64 (AMD64) OS: Linux (All) Status: NEW Severity: normal Priority: medium Component: Drivers/Gallium/radeonsi Assignee: dri-devel@lists.freedesktop.org Reporter: b747xx@gmail.com
Created attachment 107298 --> https://bugs.freedesktop.org/attachment.cgi?id=107298&action=edit HUD showing FPS drop and mem transfer
I got an lag / pause (stopping for one to +- 5 seconds) when I get transfer of memory from the VRAM to GTT and the opposite, the GTT to VRAM.
It append only on Minecraft (No problem with EVE-Online & Source Engine games), even sometime when it is not on the screen, and in that case, the whole X ui stay locked until the transfer finish. It usually go fine until the VRAM reach between 280-300MB and it start playing with the GTT.
The bug Append with: Kernel 3.17-rc2+ (did not test the RC1, 3.16 was fine) Mesa GIT newer than somewhere in the beginning of september.
Note that these don't need to be recent for the two. A old kernel with a new Mesa and a new Kernel with a old Mesa recreate the problem. Having the latest GIT of the two don't fix the problem. (I did in fact update libdrm, llvm, mesa, xf86.... after upgrading the kernel to rc2, thinking something changed and was requiring a newer mesa.
I have attached a screenshot with the Gallium hud showing the FPS and memory.
PS : I thought initially that it was the same as BUG #82050 but got requested to file another bug.